Rogue Tuning NA-Tune: MAF conversion for the 944NA!

[Rogue_Ant]

So, the majority of aftermarket performance focus (regarding engine power) has been for the 951/944Turbo, leaving out the 944NA. Gains with the 944NA are hard to come-by, and typically aren't as "impressive" as the 951.

After doing MAF conversion for the 951, and flow-benching many factory airflow meters, two things became evident: One, the 20+ year old electro-mechanical AFMs are dying, and losing their original calibration. Two, the AFM is a huge airflow restriction, and that by doing nothing besides removing that restriction we see airflow improvements.

So, I bought a 944NA to test with, and I am very pleased with the results. With our MAF kit, on an otherwise stock car, we saw an ~8% increase in HP, with that gain occuring at every RPM! Here is the back-2-back (same car, same dyno, the pulls within minutes of eachother) dyno result:



FYI, the only mod to my 85NA is the N-Tune, everything else is completely stock down to the cast-iron headers. The dyno really shows what I've felt all along - great gains at every RPM!

Since then, I've quantified other modifications for the 944NA. I removed the (supposedly) restrictive catalytic converter and stock muffler, replacing them with a straight-through 2.5" resonator, 2.5" exhaust and 951 muffler (also straight-through and 2.5"). Additionally, I picked-up an K&N air-filter, and an 4° offset camshaft key from 928Motorsports.
So, things learned:

K&N air filter made no power over a new paper filter. Again, it made 0hp & 0tq, over a standard parts retailer paper filter. So, if a K&N filter was on your list, I suggest to not bother. Furthermore, the K&N will get oil on the MAF sensor as it uses oil in the filter media - shouldn't be a real issue, but why even risk it.

The air filter is not a restriction period. We did a couple pulls with the air-filter completely removed, and again it made 0hp & 0tq difference. So, the short lesson here is just use a standard paper filter, and replace at recommended intervals.

Second thing, the improved exhaust and removing the catalytic converter, there isn't whole lot of power increase, and most of those gains are in the upper-RPMs. I would say it was worth 3-4rwhp. Though with the resonator & 951 muffler it does sound damn good!

Third, we installed the offset camshaft key, which gave a -4° shift in cam-timing. This should shift power to the higher RPMs... Well it did help keep HP/TQ up in the higher-RPMs, but was improvement was extremely limited and that was at the expense of lower-RPM hp/tq. The -4° shift only made better hp/tq after 5700rpm; everywhere else it gave up power.
So, we changed the cam timing to provide a +4° shift. This was the ticket! Power everywhere below 5700rpm was vastly improved compared to the previous runs. The drivability improvement and overall acceleration was very noticeable. Even with the advanced cam timing, the upper RPM was improved compared to stock.

Here is the stock vs modified (NA-Tune, 4° advanced timing, "cat-back" exhaust):
peak power stock: 117.6rwhp, 122rwtq.
peak power mod: 132.8rwhp, 142rwtq.

The % gains are ~13% increase in power (+15rwhp), and ~16% increase in torque (+19rwtq).
These mods are easy to do, and can be done for less than $800-900 (NA-Tune $500, offset cam key ~$20 (one pack will do two 944s), exhaust ~$300).

And finally, the before/after dyno:



The next modification I am going to try will be a reground camshaft that is fairly aggressive. I will also put on a true adjustable cam-gear to dial in the new cam.
It won't be this weekend, but maybe next.

The goal for me is to show how to make some respectable gains with the 944NA, with the minimum amount of effort and keep the cost reasonable.

[Gawernator]

Guess my K&N is just for show! Your pictures don't seem to be showing. What sort of low-end losses did you experience with the free-flowing exhaust?

[Rogue_Ant]

Originally Posted by Gawernator

Guess my K&N is just for show! Your pictures don't seem to be showing. What sort of low-end losses did you experience with the free-flowing exhaust?

Fixed the pictures - thanks!
The low-end lost a little bit from the free-flowing exhaust, but with the MAF the low-end still performed better than stock. Then adding in the cam-key really helped make use of the added flow from the MAF and exhaust.

[Gawernator]

It really is tempting.. maybe a christmas present

[Techno Duck]

Debunking horsepower claims with actual proof?!? You just reduced post frequency on the 944 forums by 50%!

[will944]

Great numbers. Wish this were around when I had my N/A car!

[Tcrate]

Can you confirm what the MAF kit entails. I am assuming the MAF unit to replace the AFM and chip correct? Also will this work on a 944S or will that require a whole different setup/development for this engine?

[FRFdave]

Hello all!
I am new to Pelican but not new to Rennlist. I have personally driven this car and although it is just a NA it still surprises me when the power comes on. The engine bay is much cleaner and the amount of restriction that is removed is impressive! The biggest surprise is that the K&N has no gains. I have always been a believer in them but after the results were in now I will only be buying them for there long lives! just my 2cents

[Rogue_Ant]

Originally Posted by Tcrate

Can you confirm what the MAF kit entails. I am assuming the MAF unit to replace the AFM and chip correct? Also will this work on a 944S or will that require a whole different setup/development for this engine?

The MAF kit includes everything needed to convert to MAF.
It comes with the bolt-in MAF pipe (bolts right to the factory air box), the actual MAF sensor, the plug-n-play wiring (plugs right into the stock AFM plug), and the chipboard with software.

The 944S/S2 is different, but is something I'm currently working on.

[minho78]

Josh, even though you provided evidence people don't believe you. You are an asset to the 944 community. We are lucky to be around you.

[Slam]

Hmmm. Should I say "FINALLY!" or would that be premature?

[Rogue_Ant]

Originally Posted by Slam

Hmmm. Should I say "FINALLY!" or would that be premature?

Nope it is done, I'm waiting on the first batch of MAF pipes, and as soon as they are here, I will put the order page up.

[plaight]

This is all done in denver right? So the sea level folk might see a few more ponies out of this

[Rogue_Ant]

Originally Posted by plaight

This is all done in denver right? So the sea level folk might see a few more ponies out of this

Absolutely. The percentage gains are the tell-tale. If your car at sea-level, dyno's say 125rwhp, then I still expect to see around 8% gain, or ~10rwhp in this case.

[mike leborgne]

Joshua, I also live in Denver could you PM me with your phone or address, would love to get together and see what you have done.
Thanks
Frenchy

[Rogue_Ant]

Mike my phone is on the website:

http://www.roguetuning.com/contact_us

I would be happy to meet up with you and show you the kit / let you drive it.

[Rogue_Ant]

A quick update.

I've decided to make better use of the FQS switch. In factory form, the first and second 4 positions are identical, with the second 4 positions also having a ~3° timing retard...
After playing with ignition timing on the dyno, I do not see the need to retard timing via the FQS switch. So, I've changed the FQS settings to now have all 8 positions enact a different fueling adjustment. This gives the end-user a lot of adjust-ability to make sure the Tune is as perfect as possible for their car without the need for additional tuning devices or piggybacks:

[v2rocket_aka944]

Originally Posted by Gawernator

Guess my K&N is just for show! Your pictures don't seem to be showing. What sort of low-end losses did you experience with the free-flowing exhaust?

If you go about the math, the modifications he has done have produced an additional ~30lb/ft at the crank over stock...huge gain in something the 944 DESPERATELY needs.

[J1NX3D]

its funny, i just watched this last month

[Dougs951]

Any chance a S2 maf kit is in the works?